MySQL优化一例

DELIMITER $$

USE `oa`$$

DROP FUNCTION IF EXISTS `F_getBuluDates_inner`$$

CREATE DEFINER=`root`@`localhost` FUNCTION `F_getBuluDates_inner`(`PuserId` INT(11), tmpdate VARCHAR(32), nowdate VARCHAR(32)) RETURNS VARCHAR(3000) CHARSET gbk
BEGIN
DECLARE buluDate,buluDateTime,LiWaibuluDates,bldate VARCHAR(3000) DEFAULT "";
DECLARE rtMsg,RuserName,maxRiZhiDate,btjrqs,blyqrq,yxblsj VARCHAR(255) DEFAULT "";
DECLARE Ra51count INT(30);
DECLARE RbeginDate,RendDate,RtmpDate VARCHAR(2550);
DECLARE u,gqcount,a21Count INT(30) DEFAULT 0;
DECLARE allReadRows,readRows,mySYL,blCount,recordCount,btjryCount,btjrqCount,yxblts,i INT(11) DEFAULT 0;
DECLARE no_more_data INT DEFAULT 0;

DECLARE my_cursor CURSOR FOR SELECT DISTINCT a2104 FROM a21 WHERE issubmit='y' AND a2104 < tmpdate AND a2104 >= nowdate ORDER BY a2104 DESC;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET no_more_data = 1;

SELECT a5204,a5205 INTO yxblts,yxblsj FROM a52 WHERE a5218="gzrz" LIMIT 0,1;    

SELECT username INTO RuserName FROM USER WHERE id=PuserId;

SELECT COUNT(id) INTO btjryCount FROM a52 WHERE a5214=PuserId AND a5218='xxxxx';   
IF btjryCount=0 THEN    

SELECT GROUP_CONCAT(a5215) INTO btjrqs FROM a52 WHERE  a5218='xxx';   

OPEN my_cursor;
FETCH my_cursor INTO maxRiZhiDate;

REPEAT 
    IF F_isWorkDay(maxRiZhiDate)=1 OR ISNULL(maxRiZhiDate) THEN
        IF NOT ISNULL(maxRiZhiDate) AND LENGTH(maxRiZhiDate)>0 THEN
            IF FIND_IN_SET(maxRiZhiDate,btjrqs)=0 THEN    
                SELECT COUNT(id) INTO recordCount FROM a21 WHERE a2104=maxRiZhiDate AND creatorid=PuserId;  
                IF recordCount=0 THEN  
                    IF DAYOFWEEK(maxRiZhiDate)=6 THEN
                        SET buluDateTime=CONCAT(FROM_DAYS(TO_DAYS(maxRiZhiDate)+2+yxblts)," ",yxblsj);   
                    ELSEIF DAYOFWEEK(maxRiZhiDate)=7 THEN
                        SET buluDateTime=CONCAT(FROM_DAYS(TO_DAYS(maxRiZhiDate)+1+yxblts)," ",yxblsj);   
                    ELSE
                        SET buluDateTime=CONCAT(FROM_DAYS(TO_DAYS(maxRiZhiDate)+yxblts)," ",yxblsj);   
                    END IF;

                    IF(CURRENT_TIMESTAMP()<buluDateTime) THEN  
                        SET buluDate=maxRiZhiDate;
                    END IF;
                END IF;                     
            END IF;  
        END IF;  

    END IF;
    IF CHAR_LENGTH(buluDate)>0 THEN 
        IF CHAR_LENGTH(bldate)>0 THEN
            SET bldate=CONCAT(buluDate,",",bldate);
        ELSE
            SET bldate=buluDate;
        END IF;
    END IF;

FETCH my_cursor INTO maxRiZhiDate;
SET buluDate='';
UNTIL no_more_data = 1
END REPEAT;


SELECT COUNT(id) INTO gqcount FROM a52 WHERE a5216=CURDATE() AND a5218='xxx';
IF gqcount>0 THEN
SELECT a5215 INTO blyqrq FROM a52 WHERE a5216=CURDATE() AND a5218='xxxxxxxxxx';  
SELECT COUNT(id) INTO a21Count FROM a21 WHERE a2104=blyqrq AND creatorid=PuserId;
IF a21Count=0 THEN
IF FIND_IN_SET(blyqrq,bldate)=0 THEN 
IF CHAR_LENGTH(bldate)>0 THEN
SET bldate=CONCAT(blyqrq,",",bldate);
ELSE
SET bldate=blyqrq;
END IF;
END IF;
END IF;
END IF;

IF ISNULL(btjrqs) THEN
SET btjrqs="";
END IF;

SELECT GROUP_CONCAT(a5108) INTO LiWaibuluDates FROM a51 WHERE a5110='y' AND F_ifInSet(a5108,btjrqs)=0 AND a5106 LIKE RuserName AND a5112='否' AND CONCAT(a5108," ",a5113)<CURRENT_TIMESTAMP() AND CURRENT_TIMESTAMP()<CONCAT(a5114," ",a5113);
IF NOT ISNULL(LiWaibuluDates) AND LENGTH(TRIM(LiWaibuluDates))>0 THEN 
IF CHAR_LENGTH(bldate)>0 THEN
SET bldate=CONCAT(LiWaibuluDates,",",bldate);
ELSE
SET bldate=LiWaibuluDates;
END IF;
END IF;       

SELECT COUNT(id) INTO RA51count FROM a51 WHERE a5110='n' AND F_getid1value2(a5105,1)=PuserId; 
IF RA51count>0 THEN 
SET u=0;
WHILE u< RA51count DO           
SELECT a5108,a5109 INTO RbeginDate,RendDate FROM a51 WHERE a5110='n' AND F_getid1value2(a5105,1)=PuserId ORDER BY id LIMIT u,1;
SET RtmpDate=RbeginDate;
WHILE RtmpDate<=RendDate DO

IF FIND_IN_SET(RtmpDate,bldate)>0 THEN 
SET bldate=F_removeFromSet(RtmpDate,bldate);
END IF;
SET RtmpDate=DATE_ADD(RtmpDate, INTERVAL 1 DAY); 
END WHILE;
SET u=u+1;
END WHILE;                      
END IF;      

END IF;  

RETURN bldate;

END$$

DELIMITER ;

DELIMITER $$
CREATE FUNCTION F_getBuluDates_new(`PuserId` INT(11)) RETURNS VARCHAR(3000) CHARSET gbk
BEGIN
    DECLARE bldate VARCHAR(3000) DEFAULT "";
    DECLARE tmpdate,nowdate VARCHAR(32) DEFAULT "";
    DECLARE yxblts INT;  
    SELECT a5204 INTO yxblts FROM a52 WHERE a5218="gzrz" LIMIT 0,1;  
    SET tmpdate = CURDATE();
    SET nowdate = DATE_SUB(tmpdate,INTERVAL yxblts DAY);  
    SET bldate = F_getBuluDates_inner(PuserId,tmpdate,nowdate);   
    RETURN bldate;
END
$$

mysql> select F_getBuluDates_new(10687);
+---------------------------------------------------------------------------------------------------------------+
| F_getBuluDates_new(10687)                                                                                    |
+---------------------------------------------------------------------------------------------------------------+
| 2016-08-04,2016-08-05,2016-08-08,2016-08-09,2016-08-10,2016-08-11,2016-08-12,2016-08-15,2016-08-16,2016-08-17 |
+---------------------------------------------------------------------------------------------------------------+
1 row in set (1.10 sec)

mysql> select F_getBuluDates(10687);
+---------------------------------------------------------------------------------------------------------------+
| F_getBuluDates(10687)                                                                                         |
+---------------------------------------------------------------------------------------------------------------+
| 2016-08-04,2016-08-05,2016-08-08,2016-08-09,2016-08-10,2016-08-11,2016-08-12,2016-08-15,2016-08-16,2016-08-17 |
+---------------------------------------------------------------------------------------------------------------+
1 row in set (13.10 sec)

mysql> explain SELECT DISTINCT a2104 FROM a21 WHERE issubmit='y' AND a2104 < '2016-08-16' AND a2104 >= '2016-08-10' ORDER BY a2104 DESC;
+----+-------------+-------+-------+----------------------+----------------+---------+------+------+--------------------------+
| id | select_type | table | type  | possible_keys        | key            | key_len | ref  | rows | Extra                    |
+----+-------------+-------+-------+----------------------+----------------+---------+------+------+--------------------------+
|  1 | SIMPLE      | a21   | range | a2104,issubmit_a2104 | issubmit_a2104 | 516     | NULL |  834 | Using where; Using index |
+----+-------------+-------+-------+----------------------+----------------+---------+------+------+--------------------------+
1 row in set (0.00 sec)